Oil well pump and the like



Aug. 22, 1944. R. L. CHENAULT OIL WELLPUMP AND THE LIKE Fild March 2o,1944 2 sheets-Sheet 1 5. 6 A 4 6&4 55

N R. L. @HFQNA ULI www , Aug- 22, 1944- 4 L. cHENAl'JLT 2,356,504

\ OIL WELL PUMP AND THE LIKE Filed March 20, 1944 2 Sheets-Shed 2 xm ljIl!!4 Sym r IHN! S- XS 62 l 3mm Z RL. QHBNAULT m fb-47@ 1 the chamberin the well.V

A cur if the pump is not This 'additional head Patented A'ugjzz, 1944 iRoy nchenmut,v ou cit Research & Development Company, Pa.,'a corporationo! Delaware hPa., assign'or to Gulf), z

Pittsburgh, f n

ippucatimmwn 2o, massi-lama 527,285, e claims. (cl, 10s-24o) Thisinvention relates to oil Wellpunipsand the like, having a displacementchamber submerged in a pool of oil in awellwhich is'altemately lle'dwith oil from the pool and with ygas under pressurefrom'the top of thewell, the oil in the chamber being displaced by the gas intorwell tubingfor delivery to thesurface ofthe ground.

Such pumps generallyinclude two, spaced, concentrically arrangedstrings'of tubing located in the usual casing ofthe well;` Theinnerstring forms anoil eduction pipe through 'which oil from thedisplacement chamber is vconducted to the top of the well while theannular space be- Y tween the tubes serves as a conduit to'deliver thetop of the Well to Theow of gas and oil is controlled and directed bymeansA ofvalves carried by the tubing inthe wellfor alternately gasunder pressure from `establishing and interrupting communication betweenthe annular gas spaceand the displacement chamber and then, forexhausting the displacement chamber ofee trappedgas; between thedisplacement chamber and the well casing. 4

yHe'retofore difficulty has been encountered with pumps of this type irlthe design of an eflcient yet simply constructed' and operatedarrangement of valves and tubing by means offwhich full andpositivejcontrol of the pumpisrobtained even under adverse conditionso'foper'ationr Ijiston, sleeve and poppet or plug'typevalves vhave beenused in these pumps but have not rfold increase in head as when theinnerand outer pump tubes are 'of onef'and [two-inch diameter, respectively,and may require forlifting purs posesa gas pressure farin excess of thepressure of thegas available for normal, continuous pump operation 1 l ii When"v this occurs itV is necessary to "unload the pump, i. e., reducethe head of yoil in the tube ing'to normal or to a Vweight of oil thatcan be raised by*- the pressure of the gasV available for Yoperating'the Dump.VY Generally this 'is accomplished throughv theprovision `of` automatickick' oi."valves at spaced, intervals 1 on theinner ltube string, .ThesevalvesV automatically admit pressure gas intothe inner tubestring at progressivelylower levels but'th'eir use isnotalways convenient, economical vior'usatisfactory. Somef Y times itmay be desirable to' completely evacuate the pump of oil into the well,asbefore pulling proven altogether satisfactorybecause of ex'cessivewear and leakage, exaggerated occasionally by excessive quantities ofsand in the oil, misalignment of the pump etc. Proper seating ol.'

poppet' and plug-type valves may not always -oc perfectly vertical.Also, when pumps of the above in a well, or when such as is known in theart, typeV are iirstfinstalled pumps are left idle in a well,V sometimesfor even a few hours, `itmayib'e dimcult or impossible to start them.'for the reason that oil 'accumulatesfin' the well v and may, -underformation pressure, seek a level in vboth the well and the pump whichisy considerably in excess of the normal, working, submergence head ofthe pump. Then, sinceftheoil in the pump is trapped bythe action ofthe'automatically closing oil inlet valve of Vthe pump, compressed,gas-admitted, to the pump for operating it must not only raise thealready abnormal head of oil in the eduction tube, but must 'alsooperatela'gainst an additional head V-of oill occasionedby"dis`placement offthe contents ofthe annulus vinto the eduction tube.

ofroll mayresult in athre'e- A further object-cntY thev inventioisthepio- 3'5" visionof valve means vf ordischarging' oil whichY the pumpor in advance of'operationor torclear the pump of undesirable orforeignfmatter.

It is an object of the presentinvention to pro vide a pump'ofpthecharacter described, with an arrangement of valves and- 'tubing' suchthat proper seating of. the valves is achieved even under adverseconditionsof operation and Ythough the tubing may deviate slightlyfromthe vertical.

' A 4further .object of the invention is the provision of a pump of thecharacter described which does'notr need kick-'oil valvesand which maybe quickly brought into operation regardless of the.

head of oil accumulatingfvinl the f tubing 'abovev the displacementchambe accumulates in the annular gas space above thedisplacementchamber, directly into the we1l,fthat is, into the space inthe well betweenthefwell casing and the pump,

A Yfurther object, Qfinelnvenub'n :eine prt;

visioniof means :forv discharging l oil accumulating yin' thedisplacementAv chamberf and inner tube i string,;as well as theoilaccumulatingvin the annulus into the well, advantageously through thestandjvalvefat the lower-end of the displacement chamber; whereby boththe tube strings of vthe pump and the displacement Vchamber maybeentirely emptied of oil Vwhile'the pump remains in position in the well.

ply Aafncltheri with the cas A still further .object 'of the inventionis the provision of balland seat valves inl a pump of the 'characterdescribed foralternately connect ing the displacement chamber with theVgas supy the valve assembly having a flow channel-therethrough fordischarging oil: from the displacement chamber-into theVVV inneror'eduction tube string for removing the oil from the well.

These and other objects are accomplished by the pump..of the presentinvention as will be apparent from the following description and ac'companying drawings wherein,

Fig. 1 is a view partly in vertical sectionl and Fig. 3 isa detailvertical .sectional view of theV lower end of the pump including aportion oi the;

displacement chamber.

Fig. 4 is a horizontal sectional view talren alongVr on their seatsthereby opening the valves and aiording communication between thepassages and the interior of the countersunk portions.

Balls I5 being of larger diameter than the width of the openings Il, areconstrained from lateral displacement out of the countersunk .portionsthrough such openings and are -further constrained from upwardlyescaping by means of 'spider Vlr-whichv is suitably positioned in recessI8 of coupling 9. Spider llris provided with a center bore of equal orgreater diameter than bore Il and concentrically arranged with respectthereto, as shown.

Coupling Ill (Figs. 2, 5 and 6) is recessed as at I9 to receive thelower end of the valve assembly body portion and has a bore 20 equal toand concentric with bore Il.V Surrounding bore line l-I of Fig. 2 in thedirection of the arrows. Fig. 5 is a horizontal sectional view takenalong line 5-5 ofFlg. 2 in the direction of the'arrows, Y

Fig. 6 is a detail vertical sectionalview taken along line H of Fig, 5inthe direction of the arrows, and

1 Fig. V'1 is a detail vertical sectional view offa modified form" ofpump valve actuating cam.

` Referring to the drawings wherein like numerais indicate correspondingparts'throughout the several views, the completefpump assembly Vis shownin Fig. 1 and consists ofV an outer stationary stringof tubing I andareciprocatox'y inner string of tubingl 2,"the two tube strings beingspaced vfrom eachother and advantageously concentrically4 arranged. YTheouter stringY of tubin'gcarries-at its lower end a valve assembly orvalve chestV represented generally by the nu'- meral3,iwhich in turnhasattached to its lower end the upper end of a displacement chamber 4. Thelower end of the Vdisplacement chamber is threaded internally andexternally for connection respectivelyvwith the upper end of'va workingl barrel 5 and, through coupling 5, with the usual pump yscreen 1, aslshown.

yThe valveV chest assembly consists of a thick walled, elongated,cylindrical body portion 3 (Figs. y2, 4 and 5), recessed and threaded atits upper end where it engages with coupling jior attachment to theend'ofthe outer tube string, and threaded at its lowerA end `for engagementwith coupling III. for connection'withlthe Vupper end ofthe displacementchamber. The body portion of Vvthe` valve assembly is provided centrally1 with.V a longitudinallyV disposed boreY orj working barrel I Iparalleling which anddisposed adjacent thereto in the wou of the'V bodyportion abouttne central bore, are a plurality of smaller bores or'tubular uid fpassageways I2.' .Passageways I2 areV advantageouslyequally spaced from'V each other and arranged with their longitudinalcenters nearer'to the wall of the central bore" than to the outside wallof thebody-portion.` The upper ends of passageways 'I2 areenlargedorcountersunk, 'ase shown at `-I 3, topommunicateV with vcen-`tral bore II through narrow rectangularfopenings Hand to receive valveballs I 5 which are adapted to seat on short tubular extensions or valveseats IIV threaded into'the ends of the .passageways at the bottoms ofeach countersin'k. Innthis position as illustrated in Fig.J 4,7`balls'I5 close the ends of the passageways and projectinto bore II,Y inaposition to be moved by a'cam adapted for reciprocation in thebore asVdescribed'hereinafter, it

being notedv thatA when the valves are closed sufficient Yclearancespace -is provided between Vthe balls and the outermost sidewalls of thecountersunk portions tognable the cam coclrl thejballs the couplingwiththe outsideof the pump, as

shown. fT he upper ends of passageways 2| are countersunk andfprovidedwith ball valves 23,

the structure, dispositionk and .operation of which aresubstantiallyidenticalwith the ball valve and seat arrangements in thevalve assembly body portion justAr described. In addition, coupling I0isL provided withaplurality of longitudinal, open fluid passagewaysu(Figs. 5 and 6) advantageously spaced midway between passages 2|.Passages 24 provide for uninterrupted communication between thedisplacement chamber and Vpassages VI2 in the body portion. In thisregard it should be noted that, as shown, the recess inV thev top endofthe body portion'and the recess in the topend of coupling I0 aresumciently deep to provide open iluid spaces or chambers 25fand 25,respectively. betweenthe ends of the body portion'and the adjacent endsof the coupling members.

-As recited, the lower en'd of coupling :Ill has connected to Hit,'inscrew threaded engagement, the top end of displacement chamber "4 whichsupports at its lower end'pump workingy barrel 5. Barrel Shasa bore 21in axial alignment with bore II and vofthesame'or less diameter. Thelower end of Ybarrel 5 is'in threaded, adjustable engagement withVa'spider-like plug 28 which is providedV with cylindrical openings 29uniformly disposed `about' a centrally located pin 30 that projects intothe barrel, 'as' shown. The plug and y the pin are secured in `adjustedposition on the end'rof this barrel bymeans of vlock-nutjl. o

kInnertube string 2` consists of a plurality of strings of pipe coupledend to endv and extending down within the outer tube string to a pointadjacent the valve assemblyY just described. Here it connects withatubular cam-shaped member 32 of slightly less diameter Ythan thediameter of bore Il.AV I'henloweren'td'of cam 32 `is tapered externallyas' at 33 to engage balls l5when the tube stringis-lowered and lcausethem to rideup ontoV the cam and assume a position in which they arecocked oil their seats to open the ends of passages I2. Internally, thelower end of cam 32 is threaded. as atV 34 to engage and support theupper end of a piston packing,"carrying tube 35 which extends throughworking barrel Il.

Tube* 35 is reducedl in VoutsideV diameter from a point L35 at; which `a1 shoulder isA formed, downwardly to the end. of the tube where it isthreaded externally-asatk3f|.v Slid'over, the reduced end 4 of tube 35to Alie against shoulder 36 are alternately, piston packinggcollars 38Yand piston pack- 4is lowered before cam of coupling 43 isfa carryingtube 46.V Tube tube is reduced -string 4through, the

- ment chamber. Y YFor the a lift cylinder of usual construction,

` ing washers 39; thea-latterbeing .formed of u' leather, fabric,

Y I5 and 23 olf their seats simultaneously.,` Instead, considering thetubes 'positioned'. asfshown Vin v is shown -in raised position, cam 4|moves below andout Fig. 2,-in which the inner tube string ofV engagementwith ballsv 23 when the inner-string 32 engages :with balls l5 to movethem oif theirseats. f

as at 42 to actuate i cam 32 holdsballs |`5 oil-their seats. sition cam4|`v will have passed below lballs 23 per- Y y pipe Blwill passdownwardly in 3 within theouter tube stringa Ji-position in which.

In'this DU- mitting them toy close the ends of passages 2|.

'Considering'then thatduring the time o f inst'all.-` v

ing the pump and 'connecting'it for operation the level of liquid'inthewell has risenM under formationpressure to ian" excessive height, liquidwill' enter'the pump throughscreen l valve 56 into the displacementchamber'through openings 41 and `pass upwardly inthe-inner tube nstring' to afheight .approximately equal -to the standing level ofliquidv in the Well.v l Under such conditions, `gas admitted to the pump`through b'etweenthe,'tube'strings and'forcethe lliquid Attached tothelower end of tube bymeans l pipe 44 which extends into the displacementchamber 4 andls joined-in turn by means of coupling 45 ywith asecondpiston working barrel 5'where it is:provided with; lateral,slotted `openings 41 immediately below which the in' diameter to form ashoulder 48 and a shortextensionl 49 threaded at its lower end. Clampedagainst shoulder by meansfof ball valve housing 50 is a second piston 46extends down lintoconsisting therein through-passages i2, space v sages'24 into the displacement 'chamber Yfrom whence it'will -be'orcedthrough openings 41 vinto the eduction tube.- However, whenvtheweight'oi the column vofoilin the' eduction tube Vbecomes ,equal tothepressure of the gas, ilow'of'liquid into the tube will cease andliquid-will notbe'ejected from'thev pump. Should .this occurjit issimply vnecessary'to lower lthe inner tube stringfuntil pin'3|!'uft'stalitt onus seaeat'whieh umethe uquid of packing material5I'and spacing colla`r'f52,

which piston is adapted'for sliding sealing en;

gagement in barrel 5; kValve Vhousing 50; formed .as shown, has :aninwardly extending annular flange 53 agalnst'which ball valve seat 54 isheld by means ofgnipple 55. Ball 56 in housing 50 operates as acheckvalve'to prevent the fluid which enters the displacement chamberand'inner tube valve from returning to the well when gas pressurelisapplied tothe Vdisplacetube string into the Y stringis moved to itsextreme lowermostposition;

If desired, one maybe inserted at different levelsin the inner tlow ofiluid down the inner tube string; With such valves in the line, aplurality of slugs of uid may be raised in the tube simultaneouslyinstead of completely removing one slug before 2 may be supported inconcentric relation to the eduction tube by attachmentv through a T pipecoupling 58 to a projection or packinggland 59 of only of which is shownat 60. Connected to the T is a pipe 6| for delivering pressure gas fromany suitable source to the pump. The inner tube string is, of course,supported in the well and adapted to be raised and lowered to actuatethe valves by attachment with the piston of the lift cylinder. g 1

In operation of the embodiment of the invention just described, theouter tube string which carries the pump cylinders well and the innertube string, or eduction tube ywhich carries the piston and valveoperating cams is next lowered andvalve assembly is lowered intoposition in the u 5B to` seat Vwhen Vit is'determin purpose of emptyingthe i contents ofthe displacement chamber and inner well, however, theinner tube y. at which time pin 3|) on plug 28 engages with ball Y v564through the valve andlifts it off its seat.

or more ball 'checkvalvesar` 50 tube string as shown in-Fig. 1, forpreventing back f I a fragment v '32,' pressure gas, stopped byY normalupper pos'ition,

in the'. pump will be forced `by` the gas'fb'ack into tube.

Vvi.s evac:uated intolthe well V'or-'i desired it maybe raised tonormal, lowered -posi ion to permit ball 'oil remaining in; thepump cbexaised.y bythe pressure of the gas available'tojoperat the pump. Innormal lowered position; A'ball 'check valve 58 barrel'lpassesdownwardly spacezsfanq passag' S124 t through` passages |2,

non tube through epenmgsgl'land their u'pjpast 'haustion' ofllquid fointhe f displacement chambeii/ as recited; the eduction `tubeiis"raisedl to` n A* Y l cam *'32 vrelea'sesballs YI5 whichimmediately'close the ends of passages I2,

thusf'shuttingoithe now of gasto the'dis'place.-

.mentgchamben and'camj4ly Ycornes]into:engagenent'with'fb'alls 23ftolift the same'from their seats yand permitthe u *Y'gasremaining'inlthedisf' placement chamber 22. 1 As thedisplacementchamber is thus relieved of pressure gas, liquid in ,thewell enters the pump Y as before but immediately as it is `determinedthat Ythe displacement chamber is filled, inner tube 2' l isloweredtonormal lower position and the liq- Y.

uid expelled' as before recited. f

.Inevent it is nothecessary or desirable to Y cam is adapted to unseatbal1s23 upon lowering of the `eduction tube' beyond its normal, working,

,lower position. In this form of the invention pin 30 maybe dispensedwith so that only the liquid in the annular spacesand passages aboveball valves 23 isexpelled fron the 'pump into the casing when theinnertube string is lowered to its extreme lowermost position.' Withv thisarrangeand ball check.

the annular space 25 and pasj throughthe lowerend of the eduction Yyermost position'juntll all" of the' oil inthe pump that the head of@ameland-inthe. vdisplacement chamber down andY into .the educ Y v u toescape vinto the" lwellY through passages24, space 26 and passages 2|and" ment liquid is accidentally or vunnecessarily expelled from thedisplacement chamber. of the; pump in initiailyfevacuatng thepump ofexcess liquid prior to regular pumpingegpergtiom The pump. of theYpresent Ainvention is simple Yin construction and operation andrelatively inexpensiveto manui'actureand repair.. .This applicationfis.a VVcontinuation-in-pari'. `of my applicationvSerial'No. 380,043, ledFebruary '.whatrclainiinj Y ,A 1

lk1. Apparatus for` pneumatically y pumping-liq-Y from wells4 whichcomprisesy an inlet for f gaseousl fluid under pressure,a-,Qdisplacement chamber adapted to be positioned inj the lqudin a well,ball ,check Vvalveineens,f or ,;v enting the j chamber of entrappedgastothewellfa second balleheck valve means for controlling theV deliv-V.ery of gaseousiiuid from said Vinlet tosaidchairi ber, avertieallyreciprocable eduction tube in communicationgwitl'rfthe lowerparto: said chamber extending vtherefrom tothe top'of the well,

` lower end of the.displacementchaxnberis pro- Y the displacementchamber to the chest and means separate from saidvalve port sealingmeans and carried by the eductiontube adapted upon recipro cation toactuate said valve port sealing means for alternately. admittingpressure gas into the chamber to displaceV` liquid therefrom into theeduction tubeor delivery to the top of the well and then exhaustingspent pressure gas from said chamber intothe well. w T

4. The subject matter of claim 3 whereinsaid valves'are ballcheckvvalves. 1

, 5.v Apparatus for pneumaticallypumpig liquids from wells comprisingspaced innei` 'and :outerstrin'gs oftubing `adapted to be positioned kina well, said innerstring of tubing forming an eduction-tubaadisplacementvchamber carried Aby the outer V,tuberstring' Iadjacent; thelower end Y thereof, vpistoni.working barrels carried by said puter tube-stri'nglabove andf below said displacementchamber," a; valved fluidYhir-pass around said upper'working barrel forestabli'shin'g' fluidcommunication between the'displacement chamber and the space between thetubes above the Y working barrel, a valved passage extending from thetop -ofY the A.displacement chamber through the'outside wall of theouter tube string,'ball check valve means in said passage,pistonscarried by the eduction'tubein position forsliding, sealing ven-Agagement with the walls of the piston working vided -with an extensionfor receiving the lower end of the eductiontube, avalve adjaentthelower. endioi the Veduction tube, ysaid tube being Vprovided withopenings in -its side .wallsin communicauopyitn V4me .lower .end of thedispiace ment, chamberabove the valve-andmeans carried byQsaiddisplacementfchamber extension forY opening .the valveWh'engtheeductionv tube islowg.- Y eredtoanextreme loweroperatingposition.vr f; 3. An apparatus;iorfpneuniatically liftingliqr uids fromwells omplisingiiler and outer strings o! tubing adapted to bePQSition-ed in,` v a well, La dlsplacementc'hamber carried byj saidouter string of tubing adjacent; the. lower end thereof said innerstringof tubing .forminganeduction tube for v,delivering liquids fromthe chamber to the top ofthe welLQa valve chest earriedby said outerstring o f tubing, anexhau'st passage-leading from the chesttothexoutside I Jffth'en;outer(stringiofiV tubing, a gas `inlet"passageiorV admitting gas.

under pressure to the chest, valve. ports and`va1ve port sealing meanscarried'.in said-chest ior controlling fluid new through saidxhaustfarid inlet Y passages, an open 'iluid Vpassageway ljading frombarrels, said bottom Vpiston and barrel closing off the lower `end ofthe displacement chamber, ball chebk valve means adjacent'the endof theeductionV tube belowthe chamber, said tube `being in open Vcommunicationabove said ball check` valve with the .bottom of said chamber, cam meansabove theipiston in the upper working barrel and carried bygthe eduction:tube for'operatingthe I valvedntheby-pass, a second' cammeans below thepiston-inthe upper working barrel and carried by the eduction tube foroperating the valve inj the passage extending fromthe top ofthedisplacementehamber through the outside wall of the outer ftubestring,and means carried by the lower working barrel for openingthe ball lcheckvalvein-theendof the eductiontube when the tube'is'lowered to anextremelower working'posi- 171011-v Y Y m 6. The subject matter'of claim1- wherein additional cam'.mea ns -is provided on the eduction tubefor'opening both 0f said valves simultane- Qusiy whenthe eduction tubeis lowered toV an extreme lowermost operating position.

Y i ROY' L.V CHENAULT.

